Two thoughts:
1. The database has not updated your records to reflect 1000/220 capability for some reason. Either stuck or an error.
2. You are very unfortunate to be placed on an ECI-based PON which are are bandwidth constrained. This is an outside possibility if Wrexham had an original ECI headend with capacity and your serving CBTs were fed from that.
My hunch is that it’s (1) and you should have Openreach look into this further using the
Availability Checker Enquiry customer form.